If my children ever wasted their inheritance(hah!)to do that to my rotting corpse the resulting diamond would be blacker than hell and twice as hot.Girls. Just toss me in a hole and head for Disneyland. I assure you I won't give a damn.

I wrote what I thought was a nice explanation of why blue diamonds are blue link. Later on, a commenter named "Blue Diamond" wrote and said as much in a comment. Then a third party emailed and demanded that blue diamond's comment be deleted. I deleted blue diamond's comment but pasted it beneath it to preserve it. Result? Everybody happy.

I was going to say that the idea of turning the deceased into a diamond is grotesque, but then I thought: It's no damn business of mine. I won't do it to anyone I love, and I doubt that anyone I love will do it to me, but if for others this makes a loss easier to bear, go for it.

When you get "cremains" back after a cremation, it's obvious that you're just getting some bones, ground up, but that's not all carbon, in fact, it's not carbon at all, if what I saw by googling is correct. The chemical composition of cremains is:

"Cremated remains are mostly dry calcium phosphates with some minor minerals, such as salts of sodium and potassium. Sulfur and most carbon are driven off as oxidized gases during the process, although a relatively small amount of carbon may remain as carbonate. The ash remaining represents very roughly 3.5% of the body's original mass (2.5% in children)."

So I ask, how does this diamond-making operation extract the carbon from the body? The diamond is so clean and clear, but what mangling of the corpse does it represent?

And that litany of elements is just a list of what's not volatile. The carbon, the nitrogen, the oxygen, the hydrogen, etc. all drift away into the ether. Carbon dioxide has some special physical properties which allow its easy separation from other gases.

Once sequestered, the carbon dioxide can be reduced back to elemental carbon or even to hydrocarbons. I came up with a formula to calculate how big of chunk of dry ice your body sequesters here (approximately 2/3 of your body weight). It seems trivial to come up with a conversion factor of how big of diamond we each could be in carats.

My link goes to NPR.org, which links to the company's website, which says: "The first step of production is to extract the different potassic and calcium compounds (about 85% of the ash volume) from the carbon by means of chemical and physical procedures. In this process the salts are solubilized, chemically cut, admixed with inert gas and afterwards anew ignited. The carbon gained in this procedure forms the basis for the subsequent synthesis in that especially constructed synthesis facility. For the synthesis the whole cremation ashes can be used, however there is only an original amount of 500gr of cremation ashes needed - independent of the weight of the subsequent diamond. During the preparation process the remnant can be steered, hence more than one diamond can be produced. According to the general conditions the cremation ashes not used in the process can be retained in order to entomb it in an urn or to scatter it. In either case the requests of the bereaved as well as the last will of the deceased will be regarded."

Can anyone explain this? I'm seeing that there is no carbon in the cremated remains.

CO2 reduction to pure diamond may be a proprietary process but the reduction of CO2 to useful hydrocarbons is commercially interesting but economically moot compared to finding pre-existing stocks. I know you're asking how to get the reduction to stop at elemental carbon not continue on; these things aren't magical, but they all involve an input of energy. Nature accomplishes the reduction of CO2 using electrons and protons with water and sunlight as raw materials.

I don't see how the diamond is composed of the carbon from the dead body.

Similar to the way a routine CH analysis is done for any new organic compound. The sample is exhaustively burned in O2, and the amounts of CO2 and water produced measured. This is essentially what Lavoisier discovered and what the Germans turned into a routine practice. I could self-link even more but that's crack-like behavior. As I said, collecting CO2 and separating it from other elements is pretty easy. But you're asking why bother -- why not cheat and provide a diamond with carbon sourced elsewhere? I don't have an answer for that one.